BMWs are well-known for their problematic cooling systems, which are often a catalyst for irreversible engine damage and a hefty repair bill. The coolant expansion tank—a crucial component responsible for holding hot engine coolant under high pressure—is a common cause of cooling system issues. Unfortunately, BMW chose to manufacture the factory E46 M3 expansion tank out of plastic. After years of exposure to high coolant temperatures, ambient engine bay heat, and chemical-rich antifreeze, the plastic degrades, eventually weakening enough to fail catastrophically.

With this issue in mind, our team of BMW enthusiasts engineered the ultimate cooling system upgrade for E46 M3 owners: a heavy-duty expansion tank built to last! Crafted from durable 5052 TIG-welded aluminum, this tank resists high temperatures and pressures without degrading over time. Unlike the fragile OEM plastic tank, Turner’s design eliminates the risk of cracking, leaking, or failure. Upgrade to our Heavy Duty Aluminum Expansion Tank Kit and say goodbye to expansion tank issues for good!

To guarantee exact fitment, the upgraded tank was designed using advanced 3D CAD modeling. All bungs, nipples, and fittings are precision-machined to ensure a secure seal with factory hose ends. Unlike other aftermarket options, this tank maintains the factory coolant capacity and includes our laser-cut logo plate at the top, providing an accurate fill level. Internal baffles are incorporated to prevent fluid cavitation, eliminating air pockets in the cooling system and avoiding false coolant level warnings during spirited driving.

Engineered for high-performance builds and daily drivers alike, this expansion tank boasts a premium wrinkle black powder coat finish for a clean "OEM+" aesthetic. This tough coating not only enhances appearance but also protects against corrosion for long-term durability. The kit includes a silicone overflow hose, a high-quality level sensor, and an OE expansion tank cap, offering a complete cooling system upgrade. Avoid the risks of the factory expansion tank—upgrade your E46 M3 today and drive with confidence!

Features & Benefits:

Durable 5052 TIG-Welded Aluminum Construction: Ensures long-term reliability and eliminates expansion tank failure. Premium Wrinkle Black Powder Coat Finish: Offers an "OEM+" appearance while preventing corrosion. Factory Coolant Capacity Retention: Maintains the same coolant level as the original design. Laser-Cut Turner Logo Plate: Provides a clear and accurate fill level indicator. Internal Baffles: Prevent the introduction of air pockets during high-performance driving. Precision-Machined External Bungs and Fittings: Ensure a perfect fit for factory hose connections. Kit Includes:

Turner Motorsport Aluminum Expansion Tank Performance Silicone Coolant Overflow Hose Expansion Tank Cap Coolant Level Sensor Product Development:

Our Heavy Duty Aluminum Expansion Tank was designed, engineered, tested, and quality inspected by our Research & Development team. Our development process includes leading-edge product technology: FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer, and rigorous long-term product testing.

Replace the Achilles heel of your factory cooling system with a stout and reliable mechanical thermostat setup.

The factory E46 thermostat housing is a combined unit featuring a plastic housing and a built in thermostat that you cannot replace separately. These plastic all-in-one units are commonly know to crack or fail causing a headache, a trip on the tow truck and possible damage to your engine.

Taking cues from the reliable M50 thermostat setup we designed a an assembly that not only converts your plastic housing into a billet aluminum unit but also swaps out the integrated thermostat for a separate replaceable thermostat. The ability to swap out thermostats separately from the whole housing opens up doors to changing thermostats to different temperature ratings based on your application while also providing lower maintenance costs. No longer do you have to replace the whole housing but just the thermostat itself.

The billet housing is designed to be utilized with E46 M3 upper and lower radiator hoses and also features -16 ORB connections for custom radiator hoses. A major upgrade from the factory and aftermarket plastic units. Our thermostat housing kit can be used by the savvy daily driver or the track hero who wants to ensure the durability of their cooling system.

Key benefits:

Uses M50/S50 mechanical thermostat for increased reliability
Option to use aftermarket colder thermostats if desired
Thermostat can be replaced separately for lower maintenance cost
Barbed hose connections for use with E46 M3 hoses or built in -16 ORB connections for custom radiator hoses
Design:

Machined out of a single piece of billet 6061 aluminum, this thermostat housing will withstand higher prolonged temperatures and abuse for performance applications
Black anodized with engraved Turner logo on the front to match the Turner Motorsports Power Steering Reservoir
Viton gasket for superior sealing performance
For use with E46 M3 radiator hoses 11537830715 and 11537830716
Kit contents:

6061 Billet Aluminum Thermostat Housing
Mechanical Thermostat
Thermostat Housing Gasket
Thermostat Harness
Optional Silicone or Rubber E46 M3 coolant hoses
Product Development:

Our Billet Thermostat Housing upgrade was designed, engineered, tested and quality inspected by our Research and Development team at Turner. Nothing but the highest level of precision and quality through leading-edge product development technology including FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer and rigorous long term product testing.

Unlike factory rubber hoses, silicone can withstand higher temperatures and pressures with minmal wear. Rubber will wear out and weaken so don't let it bite you when it counts! Silicone has been proven during extreme racing conditions and won't be the weak link that ruins your day.

This kit is specifically designed for the enthusiast that wants uprated cooling hoses, but also wants to address the heat-cycled plastic connectors and o-rings that are also prone to failure in higher mileage or older vehicles.

This E46 M3 ECS silicone hose set replaces two hoses - 
11537830716, upper radiator hose 
11537830715, lower radiator hose 

BMW S54 ECS Exact-fit Waterpipe Connecting Line

Enhance your vehicle’s performance with the BMW S54 ECS Exact-fit Waterpipe Connecting Line, crafted for precision and durability.

• Precision Engineering: Engineered to exact specifications for a perfect fit.
• Enhanced Cooling: Improves coolant flow for better engine temperature regulation.
• Durable Construction: Made from high-quality materials to withstand engine heat and pressure.
• Direct Replacement: Installs seamlessly without modifications for hassle-free maintenance.

Upgrade your BMW S54 engine with confidence using the ECS Exact-fit Waterpipe Connecting Line, delivering reliability and performance you can depend on.

Upgrade your BMW with ECS Tuning's Stainless Steel Hose Clamps, designed for convenience and durability. With various band widths and German-style T-bolts, these clamps offer easy adjustment to your required diameter. Say goodbye to dealer pricing and enjoy the quality you love at ECS Tuning.

• Full stainless steel construction
• Various band widths available
• German-style T-bolts for easy adjustment
• Convenient solution for hose clamp replacement

Upgrade Your BMW Maintenance with Stainless Steel Hose Clamps from ECS Tuning

ECS Tuning introduces premium full stainless steel hose clamps, offering superior quality and convenience for your BMW maintenance. Avoid dealership delays and overpricing by choosing from a selection of band widths, ensuring you receive top-quality hose clamps without overpaying.

Key Benefits:

• Premium full stainless steel hose clamps
• Various band widths for enhanced convenience
• High-quality alternative to dealership pricing
• Readily available stock eliminates waiting time

ECS Tuning 304 Stainless Steel Hose Clamps

Once again, ECS Tuning has found a way to make life easier for working on your car. Need new hose clamps but don't want to wait to order it from the dealership or pay more than you should for a hose clamp? That's where we come in! These are full 304 stainless steel hose clamps with various band widths for your convenience. They are German style using T-bolts to adjust in size to your required diameter. Never pay dealer pricing again, but still get the quality you love here at ECS Tuning.

• Made from high-quality 304 stainless steel for durability
• German-style design with T-bolts allows for easy size adjustment
• Various band widths for versatile use
• Avoid dealership pricing without compromising on quality
• Perfect for BMW enthusiasts seeking affordable yet reliable hose clamps

Includes connector housing with terminals and seals. Commonly used for the coolant level sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 61132359999 - Commonly used for the coolant level sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943